In mid-October, I walked around marveling at the outstanding color of one of our earliest trees to exhibit excellent fall color, the ash (Fraxinus spp.) And I realized, for many homeowners, this might be the last time they can enjoy the spectacular fall display of an ash tree. What I am referring to is the loss of our native ash trees to the emerald ash borer (EAB).
For some, this article might seem like a horse leaving the gate before the race has even started, as you probably haven't seen the likes of this pest in your community. And yet for others, it may be all too late.
When EAB is confirmed for a county, ash trees are considered to have a 98 percent mortality rate. One option to keep your ash tree alive is to treat it with systemic insecticides. For homeowners comparing the cost of treating the tree indefinitely with the cost of cutting down the tree, many have opted for removal. So like the chestnut and elm, the ash tree will become more synonymous with a street name rather than a landscape tree.
Yes, ash trees are overplanted throughout American cities, but they were selected for a reason. Ash trees perform relatively well in urban and residential conditions, and they have excellent varieties of yellow, red-purple and scarlet fall color.
EAB is here today, but what is on our radar? Well, it's hard to tell, because as with most invasive species, they catch us unaware. Some invasive species that you may be hearing about are Asian longhorn beetle, thousand cankers disease and spotted lanternfly.
What can you do to stop the spread of invasive species? With all the campaign slogans flying around right now, here's another one for you "Don't Move Firewood." The movement of firewood is a great vector for transporting invasive species, and it is how EAB got to Illinois from Michigan.
Instead of bringing firewood on a camping trip, purchase what wood you may need at the location you'll be burning it. Practice proper disposal of cut timber, especially any plant species that might harbor invasive pests.
Regardless whether you wish to treat your tree or have it cut down, hire tree care professionals that are licensed applicators, insured and registered with your municipality. Also, make sure that they follow proper disposal of your landscape wastes.
By the time you read this, ash trees have shed their leaves and entered dormancy. However, I encourage you to take some time next year and enjoy a native landscaping tree that is likely on its way out the door.
Are you unsure if your county has EAB? Check out the Illinois Department of Agriculture website dedicated to this non-native pest at www.illinoiseab.com, or contact your local Extension office.